Relief workers reported some storm survivors were being given spoiled or poor-quality food rather than nutrition-rich biscuits sent by international donors, adding to fears that the ruling military junta in the Southeast Asian country could be misappropriating assistance.

U.N. officials warned that the threat was escalating for the 2 million people facing disease and hunger in low-lying areas battered by the storm unless relief efforts increased dramatically.

Ten days after the tempest, reaching the worst-affected areas was getting more difficult.

Checkpoints manned by armed police were set up Tuesday on roads leading to the Irrawaddy River delta and all international aid workers and journalists were turned back by officers who took down their names and passport numbers. Drivers were interrogated.

"No foreigners allowed," one policeman said after waving a car back.

Supplies piled up at Yangon's main airport, which does not have equipment to lift cargo off big Boeing 747s. It took 200 Burmese volunteers to unload by hand a plane carrying more than 60 tons of relief supplies, including school tents, said Dubai Cares, a United Arab Emirates aid group.

A report from a Tuesday meeting of the U.N. center overseeing logistics said the airport was a bottleneck in the aid effort. "Discharging operations at Yangon airport are hampered by limitations of handling equipment, fuel availability and worsening weather conditions," it said.

The report said Britain's Department for International Development had offered to send in machinery for unloading jumbo jets and other aircraft.

With rain falling on Yangon on Tuesday and downpours predicted later this week, aid officials also said there was not enough warehouse space to protect the supplies beginning to flow in after the regime agreed to accept foreign help.

Even the quicker pace is not enough, U.N. officials warned.

"We fear a second catastrophe (in Myanmar) unless we're able to put in place quickly a maximum of aid and a major logistical effort comparable with the response to the (2004) tsunami," said Elisabeth Byrs of the U.N. Office for Humanitarian Affairs.

The tsunami killed more than 230,000 people in a dozen nations around the Indian Ocean, prompting the largest relief operation ever known. Tens of thousands of aid workers poured into devastated areas and the world community donated billions of dollars.

Myanmar's state television said the number of confirmed deaths from Cyclone Nargis had risen by 2,335, to 34,273, and the number of missing stood at 27,838. The United Nations estimates the actual death toll from the May 3 storm could be between 62,000 and 100,000.

Some victims and aid workers said that in many cases spoiled or poor-quality food was being given to survivors.

A longtime foreign resident of Yangon told The Associated Press that angry government officials were complaining that high-energy biscuits rushed in on the World Food Program's first flights were sent to a military warehouse.

Those supplies were exchanged for what the officials described as "tasteless and low-quality" biscuits produced by the Industry Ministry to be handed out to cyclone victims, the resident said, speaking on condition of anonymity because identifying himself could jeopardize his safety.

A spokesman for the military regime would not comment.

U.N. spokeswoman Michele Montas said that while Secretary-General Ban Ki-moon had expressed concern about food aid being diverted to non-cyclone victims, so far there was no evidence that was happening.

"It is a fact that a very small percentage of victims so far have received the aid, but from yesterday until today ... the situation has improved in terms of the delivery," she told reporters in New York.

CARE Australia's country director in Myanmar, Brian Agland, reported problems with some rice going to survivors.

He said members of his local staff brought back samples of rotting rice that was being distributed in the Irrawaddy delta.

"I have a small sample in my pocket, and it's some of the poorest quality rice we've seen," he said. "It's affected by salt water and it's very old."

It was unclear whether the rice, which Agland described as dark gray in color and consisting of very small grains, had come from the government or from mills or warehouses in the delta.

"Certainly, we are concerned that (poor quality rice) is being distributed," Agland said by telephone from Yangon. "The level of nutrition is very low."

The military, which has ruled Myanmar since 1962, has taken control of most supplies sent in by other countries.

Among those are the United States, which made its first aid delivery Monday and sent in another cargo plane Tuesday packed with blankets, water and mosquito netting. A third shipment was en route.

The head of Myanmar's navy, Rear Adm. Soe Thein, told Adm. Timothy J. Keating, commander of the U.S. Pacific forces, that basic needs of storm victims were being fulfilled and that "skillful humanitarian workers are not necessary," according to state television.

Secretary of State Condoleezza Rice said Washington was pressing the junta and its foreign allies to allow in not only food and supplies but disaster relief experts.

"We are doing everything we can, because this is a humanitarian issue, not a political issue," she said. "We want to make very clear that our only desire is to help the people of Burma."

Survivors are jamming Buddhist monasteries or camping in the open. Drinking water has been contaminated by fecal matter, and dead bodies and animal carcasses are floating around. Food and medicine are scarce.

The international Red Cross said its delegation in Myanmar found an urgent need for more medical supplies in the Irrawaddy delta.

"During the cyclone, many people held onto trees to avoid being blown away," Red Cross official Bridget Gardner said. "They were almost 'sand blasted' by dirt and saltwater; (many) lost the top layer of their skin and it's important that these injuries are treated before infections can set in."